The present invention relates to a tube plug, and more particularly to an expandable tube plug which includes means to clean the tube prior to effecting a fluid tight seal by means of expansion of the plug.
In some applications, such as in a condenser having tubes which carry refrigerant or other fluids, it is useful to provide a plug for the tubes to effectively seal the tubes against fluid loss, which plugs can be removable, rather than to effect a seal such as by crimping or soldering or other means which might require destruction of the tube to remove the effect of the plug.
U.S. Pat. No. 4,310,029 discloses an expandable plug for use in effecting a fluid-tight seal in a tube which includes a compressible (and expandable) sleeve located between a rigid cylindrical member and rigid sleeve. A bolt extends through the two sleeves and is threaded into the cylindrical member to apply compressive force to the compressible sleeve causing the sleeve to expand radially outwardly into fluid-tight sealing relation with the inner wall of the tube and radially inwardly into fluid-tight sealing relation with the bolt shank thereby protecting the bolt threads from contamination and corrosion. An eccentrically mounted disk is provided at the remote end of the cylindrical member to lock this member against rotation during installation of the plug.
While such a device is effective as a tube plug, in the course of using such a device it is necessary to first clean the interior of the tube, such as by brushing or scraping the interior of the tube with an abrasive material. After the tube has been cleaned, the plug can then be inserted and sealed.